Answers
1

Writing, agriculture, and centralized government first appeared in Eurasia and North Africa.

It is not the case that societies on the different continents were comparable to each other until 3,000 B.C., whereupon western Eurasian societies suddenly developed writing and began for the first time to pull ahead in other respects as well. Instead, already by 3,000 B.C., there were Eurasian and North African societies not only with incipient writing but also with centralized state governments, cities, widespread use of metal tools and weapons, use of domesticated animals for transport and traction and mechanical power, and reliance on agriculture and domestic animals for food.